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L. 0. ORTON. CUTTER FOR PLANING MACHINES.

Patented Oct. 16, 1883.

I [TLUILZOIC' Wziinestses;

N. PETERS. PMloUmc-graphar. Wixhingk-m I v C UNITED STATES PATENT OFFICE.

LYMAN O. ORTON, OF PHILADELPHIA, PENNSYLVANIA.

CUTTER FOR PLANlNG-MACHINES.

SPECIFICATION forming part of Letters Patent No. 286,633, dated October 16, 1883, Application filed June 4, 1883. (No model.)

To cuZZ whom it may concern: 1

, Be it known that I, LYMAN OSGOOD ORTON, a citizen of the United States, residing at Philadelphia, in the county of Philadelphia and State of Pennsylvania, have invented a new and useful improvement in the cutting edge of the revolving bits or planing-cutters of powerplaning machines for planing wood, of which the following is a specification.

My invention relates to improvements in the cutting-edge of the revolving bits or cutters of wood-planing machines in which 'the wood advances to the cutting-edges of the bits in a line tangent to the circle performed by the latter; and the objects of my improvement are, first, to accomplish a greater quantity of improved work in a given time than is possible with the ordinary bit in the same time with the same machine; second, to provide a stronger, straighter, more endurable, and more perfect edge for the cutter-bits of wood-planing machines than ever before known or used; third, to provide bits or cutters the cutting-edges of which can be made parallel with their axis of rotation and true to the surface of the board in process of planing by grinding while in motion and in working position, or otherwise. I attain these objects by making the back part of the bit (which follows and supports the cutting-edge) of circular form, to conform to the circle of the radius of the circle described by the cutting-edge thereof, in the manner illustrated in the accompanying drawings, in which- 1 Figure l in an enlarged exaggerated view of the end of my improved bit, showing the circular form of the back edge of the latter,

which comes in contact with and smooths the planer-surface of the advancing wood after the latter has been out and planed by the sharp edge, which is formed on the front of and preceeding the circular-curved back edge. Fig. 2 is a plan view of the bit, showing the bevel for the clearance and circular form of the back edge, which latter is'my improvement. Fig. 3 is an end view, similar to Fig. 1, of a working-size bit, showing the relative proportions of my improvement contained in the sector of the circle between the two radial lines A and B. Fig. i is an end view, similar to Figs. 1 and 3, showing three hits attached to thehead H, as in the act of cutting and planing the ing and wood W, and illustrating my improved bit in its performance of its double function of superior cutting and smoothing the wood at the same time, the circular line L showing the radius of the cutting-edge of the bit and themanher in which the latter passes through andv over the wood in its act of cutting and smooth ing the latter.

Similar letters refer to similar parts throughout the several views.

The construction of my improvement is very simple and easily understood when its great merit is known and appreciated. It can be formed upon any of the ordinary bits by Simp y ing edges of the bits while in motion and in working position, in like manner as has been done for the purpose of truing up the knives of rotary cutters into lines parallel with the axis of the latter; but after such process of truing up the edges of the ordinary cutters the circle has been filed off, leaving an acuteangled edge, while I grind'or form the edges into a circular form for a special purpose to accomplish an important object, and by a means which has hitherto been considered as dulling the edges of the cutting-bits, and thus rendering them inoperative; butI have discovered and practically demonstrated the fact that the circular form of the heel or back edge of the knife-bit is the best form for wood-planing machines for the following reasons: first, the form of the back edge, D, Figs. 1, 3, and 4, being curved, the bit enters the wood with the heel D pressing slightly upon the latter, in likemanner as a gouge inthe act of carving wood, thus pressing the fiber of the grain of the wood down or from the cutting-edge of the bit, thus performing the several functions of relieving the cutting-edge by holding the wood back from drawfollowing after the bit, and smoothing the wood by the slight rubbing-pressure causedby the slight movement of the advancing wood while the cutter is'revolvin'g at many times greater speed, and presenting a true, perfectly-formed, and well-supported edge to the work, which edges or bits, being true, can be multiplied to any desired or required number of bits necessary to plane the wood smooth at a speed of two hundred feet per minute without the usual'liability of breaking or dull ing the bits, while with the ordinary bits the holding a grinding-surface to the-revolvsharp acute-angled edges of the bits become dull and out of true with their axis of rotation; and when forced to do more work than one bit can accomplish, then the irregularities of the edges of the bits are expressed in the rough irregular surfaceof the work done.

Hence, while it is practicable to plane smoothly two hundred lineal feet of lumber with my improved bit per minute continuously, it is not possible with the ordinary bit, with its acuteangled edge, to plane as smoothly more than forty, or at most fifty, lineal feet per minute with the same machine running the cutterhead at the same speed, and the work becomes more rough as the bits become dull and irregular on account of the turning and breaking of the acute'angle of the cutting-edge.

By a comparison of the form of the edges of my improved bits (shown in Figs. 1, 2, 3, and 4) with those of ordinary bits it will be seen ,that the cutting-edge of the bit is supported by my improvement and sustained in the circular line of its motion, thus preventing the drawing back and breaking off of the sharp edge, (as in the ordinary bit,) and, further, the form of the edge conforming to the circular motion, and the short curvilinear surface of my improvement, having a slight rubbing contact upon the wood, serves to grind the surface of the bit toward its axis of rotation, thus acting as a self-sharpening process while at work, thus aiding greatly in maintaining the sharp edge of the bit, and thus facilitating. the quantity and quality of the work, making it practicable for the same number of work men with the same machine to perform a greater quantity of the same work in the same time than could. be done with the ordinary bit hence the advantages gained by my simple improvement are obvious.

I am familiar with the great variety of wood working machines, and especially wood-planing machines, having been engaged directly in the manufacture of the latter for many years, and have examined and tested all of the prac tical forms of planer-bits which have come to -my notice, especially those designed for planing smooth, flat surfaces, and am also familiar with the constructionand operation of the bits of planing-machines generally. These forms of bits, which are special and are beveled to an acute angle by grinding off the circle from the edge backward, and having the same ob-. jectionable features of the acute-angled edge of the ordinary straightedged bit without the advantages of the simplicity of the latter, have not been adapted to general use, and are not capable of accomplishing as much work in the same time as the ordinary straight bit.

The tonguing and grooving bits, formed of circles smaller than the circle of the radius of their rotation, do not act in conformity with the latter circle, (in like manner as does my improvement,) and therefore do not serve the purpose of supporting and sharpening the bit while in operation, and could not serve such purposes without my improvement, and are not practical for planing wide smooth surfaces. I have mentioned those forms of bits for the purpose of explaining the difference between a circular bit set to one side of the center of rotation and not rotating upon its own axis and my improved bit, which has its circular form coinciding with and rotating around its own axis.

If a circular cylinder were used with grooves cut in its periphery parallel with its axis to form the bit, in like manner as a certain kind of reamer, then the cylindrical circle and surface would be too great, and the wood would wedge under the cylindrical. surface and jam and choke the machine, while with my improved bit the circular surface is very smallonly sufficient to accomplish the great advantages herein set forth.

I am aware that prior to my invention bits of planing-machines have been ground to an edge parallel with their axis of rotation, in like manner as my improvement, by turning the bits while in their working position, and I have done the same myself but supposing that the bits were thus dulled and unfit for work, I dressed the circle formed by the grinding proc'ess off with a file or emery-grinder, leaving the acute-angled edge similar to that of the ordinary bit, as did all others in all cases within my knowledge, and as the thousands of the machines now in use of my own manufacture and that of other builders will attest; and having practically demonstrated its usefulness and its immense value in producing superior work and economizing time, money, and machinery, I now desire a patent for my simple improvement, which, owing to its extreme simplicity and great usefulness, I believe is destined to rank among the most valuable of the modern improvements in planing-machinery. I disclaim anything which has heretofore been known or used, and confine my claim to the novelty of the peculiar circular form'of the edge of the bit, which acts upon the wood in such manner as to partly'smooth the latter while in the act of cutting it, and at the same time the process of smoothing the surface of the wood rubs and wears the circular part of the edge which follows the sharp cutting front corner of the latter, and thus serves to sustain and sharpen the front corner or cutting part of the edge of the bit; and the circular part, forming amore obtuse angle with the front part to form the sharp cutting corner or edge, makes the latter stronger and more durable to out through knots and hard wood than the more acuteangled cutting-edge of the ordinary bit, in which latter the back part of the edge, being beveled and cut away from the circle of the radius of the cutting front corner, leaves the latter unsupported, and hence the cutting part is nicked and crumbled off by contact with knots and hard substances in the wood, and is thus dulled, rendered out of order by nicked uneven edges much sooner than bits with my improved edge, which latter is stronger and protected from nicking and dulling by the circular part, which follows and supports 'the front corner or cutting-edge directly in its circular path and motion in the act of cutting the wood.

What I do claim, broadly, as my invention,

' anddesire to secure by Letters Patent, is

In combination with the rotary bit 0 of -wood-planing machines-which bit is made of metal, flattened and elongated into suitable form and secured to the cutter-head H, and having the back corner of the outer edge beveled or cut away, so as to provide eearancethe circular edge or part 1), formed on the outer edge or surface of the bit, making that part of the outer edge of circular form be tween the lines A and B, or between the corner of the beveled part and the front corner or cutting-edge, as indicated by the said radial lines A and B, constructed and arranged to op- 20 erate in the manner and for the purpose substantially as illustrated and described.

LYMAN OSGOOD OBTON.

Witnesses:

HENRY H. SUPLEE, L. H. BERRY. 

